On-line building damage assessment based on earthquake records

Abstract

This paper deals with the applicability of system realization using the information matrix (SRIM) system identification technique combined with moving time windows (called WSRIM) in order to evaluate the time-varying dynamic properties and damage of a building based on its real earthquake records considering the soil–structure interaction effect. Successive short segments of inputs and their corresponding output signals are selected and structural properties exhibited during that segment of time are identified. Both numerical simulation and real earthquake response measurements from several floors and foundations are utilized to verify the accuracy of the proposed time-varying system identification technique. In addition, the seven-storey reinforced concrete building of the Civil and Environmental Engineering Department at the National Chung Hsing University experienced moderate structural damage during the 1999 Taiwan Chi-Chi earthquake. This paper evaluated the time-varying modal parameters of this building on the basis of records of its acceleration response to the Chi-Chi earthquake main shock and its numerous after-shocks. It is proved that the proposed system identification technique is useful for real-time dynamic property estimation and damage assessment of buildings.